Generally, a semiconductor circuit is tested by supplying test patterns stored, in advance, in a tester memory in an LSI tester to the semiconductor circuit. When a plurality of tests are conducted, test patterns corresponding to the number of tests should be stored in the tester memory.
The functions of the semiconductor circuit have been complicated in recent years, and the number of tests to be required has also been increased. However, the capacity of the tester memory is limited, which leads to a problem that all test patterns cannot be stored in the tester memory and thus the tests cannot be adequately conducted.